Establishment of diagnostic significance of high-signal intensity on T2 weight MRI in temporomandibular joint disorders

为探讨颞下颌关节紊乱病(TMD)T2加权像高信号(关节积液；JE)的意义，进行了临床和实验研究。临床研究包括测定滑液中总蛋白和促炎性细胞因子(IL-1β、IL-6、IL-8、肿瘤坏死因子-α)及其受体，并对关节镜下获得的滑膜组织进行组织学和免疫组织化学评价。根据高信号区的体积与JE分级(0~3)进行比较。关节镜检查结果(滑膜炎、粘连、退行性变；评分0-10)也与JE分级进行比较。结果显示，只有关节镜下发现的滑膜炎症程度与JE有显著相关性。滑液中总蛋白、IL-6、IL-8浓度与乙脑呈正相关。组织学上，滑膜组织的滑膜炎症程度与乙脑的3项指标中的2项(滑膜衬里细胞层和炎性细胞浸润)有显著相关性。为了探讨JE的解剖学因素，我们比较了正颌外科手术患者手术前后的MRI表现。结果表明，关节内紊乱与关节囊内炎症，尤其是滑膜炎症密切相关。JE可能反映了上调的蛋白质和细胞因子，并释放到滑液中。关节间隙的增大可能是JE发生的解剖学因素。乙脑可能是指关节内的炎性反应(滑膜炎)，可能具有重要的诊断价值。

Clinical and experimental studies were undertaken in order to elucidate the significance of high signal intensity (joint effusion ; JE) on T2 weighted MRI of the temporomandibular joint disorders (TMD).Clinical research was measurement of total protein and pro-inflammatory cytokines ( IL-1β, IL-6, IL-8, TNF-α) and their receptors in synovial fluid as well as histological and immunohistochemical evaluation of the synovial tissue obtained arthroscopically. These samples were compared with JE grade (0-3) according to the volume of high signal area. The arthroscopic findings (synovitis, adhesion, degenerative chage ; scored 0-10) were also compared with JE grades.The results showed that only the degree of synovitis detected arthroscopically had significant correlation with JE. The concentration levels total protein, IL-6 and IL-8 in synovial fluid had positive correlations with JE. Histologically, the degree of synovitis in synovial tissue showed significant relationship with JE in 2 items (synovial lining cell layer and inflammatory cell infiltration) of 3 items. To investigate the anatomical factor of JE, the pre-and post-operative MRIs were compared in orthognathic surgry underwent for mandibular progenia patients. The positive JE were depicted in joints with more movement of the condyle than less movement.These results suggest that JE in TMD (internal derangements) were closely relative with intra-capsular inflammation, especially synovitis. JE might reflect the protein and cytokines up-regulated and released into the synovial fluid. The increased joint space may contribute JE development as anatomical factor. JE probably mean the inflammatory reaction in the joint (synovitis) which might be significant diagnostic value.